$\"\"$

The pair of points $\"\"$ and $\"\"$

The distance formula in polar coordinates is $\"\"$ .

Substitute $\"\"$ and $\"\"$ in the distance formula.

$\"\"$

Even odd property : $\"\"$ .

$\"\"$

Trignometric property : $\"\"$ .

$\"\"$

Trignometry property : $\"\"$ .

$\"\"$

The distance between each pair of point is $\"\"$ .

$\"\"$

The distance between each pair of point is $\"\"$ is $\"\"$ .